//STATE PROGRAMMING IS WHAT I DID HERE
#include <LiquidCrystal.h>
#include <Keypad.h>

#define LINE_R 1
#define LINE_Y 6
#define LINE_B 13
#define MAX_KM 4000
float LINE_R_CURRENT = MAX_KM;
float LINE_Y_CURRENT = MAX_KM;
float LINE_B_CURRENT = MAX_KM;

const int rs = 12, en = 11, d4 = 10, d5 = 9, d6 = 8, d7 = 7;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};
char getterR[4] = {'1', '4', '7', '*'};
char getterY[4] = {'2', '5', '8', '0'};
char getterB[4] = {'3', '6', '9', '#'};
byte rowPins[ROWS] = {5, 4, 3, 2}; // connect to the row pinouts of the kpd
byte colPins[COLS] = {A3, A2, A1, A0};   // connect to the column pinouts of the kpd
Keypad kpd = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);
bool isR = false, isY = false, isB = false;

void setup() {
  lcd.begin(16, 2);
  pinMode(LINE_R, OUTPUT);
  pinMode(LINE_Y, OUTPUT);
  pinMode(LINE_B, OUTPUT);
  digitalWrite(LINE_R, HIGH);
  digitalWrite(LINE_Y, HIGH);
  digitalWrite(LINE_B, HIGH);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Underground ");
  lcd.setCursor(0, 1);
  lcd.print("Fault ");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Detection System");
  lcd.setCursor(0, 1);
  lcd.print("By Samuel Dintui");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Bitrus Reg Numb:");
  lcd.setCursor(0, 1);
  lcd.print("16/05/05/181");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Supervised By  ");
  lcd.setCursor(0, 1);
  lcd.print("Engr. Dr. Jafaru");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Usman           ");
  lcd.setCursor(0, 1);
  lcd.print("                ");
  delay(2000);
  kpd.addEventListener(keypadEvent);
}

void loop() {
  char key = kpd.getKey();

  if (key) {//STATES LOGICS
    for (int i = 0; i < 4; i++) {
      if (key == getterR[i]) {
        isR = true;
        isY = false;
        isB = false;
        LINE_Y_CURRENT = MAX_KM;
        LINE_B_CURRENT = MAX_KM;
        handleKeyPress(i, LINE_R_CURRENT);
      } else if (key == getterY[i]) {
        isY = true;
        isR = false;
        isB = false;
        LINE_R_CURRENT = MAX_KM;
        LINE_B_CURRENT = MAX_KM;
        handleKeyPress(i, LINE_Y_CURRENT);
      } else if (key == getterB[i]) {
        isB = true;
        isY = false;
        isR = false;
        LINE_Y_CURRENT = MAX_KM;
        LINE_R_CURRENT = MAX_KM;
        handleKeyPress(i, LINE_B_CURRENT);
      }
    }
  }
  displayRYB(LINE_R_CURRENT, LINE_Y_CURRENT, LINE_B_CURRENT, isR, isY, isB);//STATE DEPENDER
  digitalWrite(LINE_R, isR ? LOW : HIGH);
  digitalWrite(LINE_Y, isY ? LOW : HIGH);
  digitalWrite(LINE_B, isB ? LOW : HIGH);

  delay(200);
}

void handleKeyPress(int index, float &lineCurrent) {
  lineCurrent -= 1000 * (index + 1);
  if (lineCurrent < 0) lineCurrent = 0;
}

void displayRYB(float r, float y, float b, bool isR, bool isY, bool isB) {
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("R:" + String(int(r)) + ", Y:" + String(int(y)) + ", B:" + String(int(b)) + "  ");
  lcd.setCursor(0, 1);
  lcd.print(String((isR && isY && isB) ? "FaultSystem:OFF" : isR ? "R-line Fault:OFF" : isY ? "Y-line Fault:OFF" : isB ? "B-line Fault:OFF" :  "All working:ON"));
}

// Taking care of some special events.
void keypadEvent(KeypadEvent key) {//STATES LOGICS
  switch (kpd.getState()) {
    case HOLD:
      for (int i = 0; i < 4; i++) {
        if (key == getterR[i] || key == getterY[i] || key == getterB[i]) {
          isR = true;
          isY = true;
          isB = true;
        }
      }
      break;
  }
}